Frozen lobster method



Patented Mar. 28, 1950 FROZEN LOBSTER METHOD M. Altenliurg, Portland,Maine, assignor tn GE's Incnrporated of Portland, Maine, "Portland,Mainaga corporation of Maine Nip. Drawing. Application August- 7,1947,Serial No. 767,361

3 Claims 1 This invention relates to a method of preparing lnbsters forcold storage and for-storing thesame and to the novel treated productthereby prodnced.

It. a familiar fact that lobster meat has. its optimum flavor andtenderness when cooked and eaten immediately after it has been removedfrom the ocean. Preservation of the lobster alive after removal from theocean is diflicult and costly, particularly during shipment whichrequires complicated and heavy shipping containers, careful handling,and also fast, expensive transit because the time interval during whichthe lobsters can be kept alive in shipping containers is only a few daysat the most. Air shipment is even more expensive. Furthermore, eventhough this expensive treatment keeps the lobster alive during storageand shipment, the qualities of tenderness and taste disappear rapidlywhen the lobster is denied its normal diet of sea water and sea foods.

Nevertheless, despite the disadvantages of live storage and extensiveefforts to overcome them, live storage has up to now been the mostsatisfactory for preserving this optimum flavor and tenderness oflobster. Once the lobster meat is cooked, it rapidly toughens, losestaste and discolors in storage, whether stored by canning, quickfreezing or otherwise or in or out of the shell. Attempts have been madeto preserve the lobster by quick freezing it live or raw in the shellbut this method has been unsatisfactory for the peculiar reason that thefreezing causes the meat to adhere to the shell unnaturally and sotenaciously that, even after the lobster is cooked, it is almostimpossible to get the meat out of the shell.

By this invention I am enabled to overcome these difficulties and toprepare lobsters for cold storage by a novel method which causes themeat to retain the taste, tenderness and color of fresh lobster duringvery long periods of cold storage without adhering to the shell.

In the practice of the invention, live lobster, or fresh raw lobster inthe shell, is heated for a brief period just suflicient to product acooking, which is in effect a searing, of only the shell and the surfaceor skin of the meat next to the shell, and the so treated lobster isthen quick frozen. I have found that the physical or chemical change inthe surface of the meat produced by this preheating effects a separationof the meat from the shell of the lobster such that the meat is notobjectionably adhered to the shell by the quick freezing or subsequentcold storage but remains loose therein and readily slips whole from theshell when the lobster is subsequently cooked. it have further foundthat the-meat ofthe so altered and cond-i tioned, frozen lobster willretain unchanged all its: initial, fresh properties-after long periodsof cold storage so that when subsequently cooked it has the taste,tenderness and color of fresh lobster- This keeping quality I attributein part to the searing action of the pre-heating-on==the-s1n'- face ofthe meat which I believe has the desirable effect of sealing the naturaljuices in the meat.

The preferred heat treatment is an immersion of the lobster in boilingwater for an interval of not less than fifteen seconds nor more thanfive minutes, depending on the shell thickness, the heating period beingjust sufficient for the heat to penetrate the shell and to produce asearing or cooking of the surface of the meat next to the shell butinsuificient to cook, even partially, the meat below the surface, whichremains raw. For a one pound lobster, the average optimum heating periodin boiling water at atmospheric pressure has been determined to be aboutone and a half minutes. The optimum time is generally less for a smallerlobster and greater for a larger lobster because of lesser and greateraverage shell thickness, respectively. If the lobster has just grown anew shell, the optimum time of heating is generally less than theaverage and if the shell has grown abnormally thick and hard, theoptimum time of heating may be longer than the average. Other types ofheating may be employed, for example, steam heating, the time of heatingbeing shortened or lengthened according as the heating temperature isabove or below about 212 F. Web heat is preferable to dry heat as thelatter tends to dry out the shell undesirably, although dry heat may beused, for example, a radar oven.

After heating, the lobster is cooled and subjected to quick freezing,for example, at a temperature of about 15 to 25 F. Preferably, thecooling and freezing take place promptly after completion of thepre-heating step. The lobster should be placed in a substantiallymoisture-proof container such as a carton or wrapper either before orafter freezing to protect it against dehydration and freezer burn andthe lobster thus prepared and frozen can be kept almost indefinitely incold storage, for example at about 5 F. When subsequently cooked by anyof the conventional methods, the meat has the taste, tenderness andcolor of lobster cooked live and is unadhered to and slips freely fromthe shell.

The invention is considered particularly significant as applied tolobsters of the crawfish variety such as are caught off the coast ofMaine and without cooking the interior meat, thereby loosening the meatfrom the shell, then cooling and rapidl freezing the lobster.

2. The method of preparing fresh raw lobster in the shell for coldstorage which comprises heating the exterior of the lobster in thepresence of moisture just sufficiently to sear the surface or the meatnext to the shell without cooking the interior meat, thereby looseningthe meat from: the shell, then cooling and rapidly freezing the lobster.

3. The method of preparing fresh raw lobster in the shell for coldstorage which comprises immersing the lobster in boiling water at about212 F. for a period of from 15 seconds to 5 minutes, thereby searing thesurface of the meat next to 4 the shell without cooking the interiormeat and thereby loosening the meat from the shell, then cooling andrapidly freezing the lobster.

WILLIAM M. ALTENBURG.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 969,238 Wright Sept. 6, 19101,016,627- Higgins Feb. 6, 1912 2,151,967 Hedreen et al Nov. 28, 19392,403,871 McBean July 9, 1946 FOREIGN PATENTS Number Country Date10,682/27 Australia Nov. 14, 1928 OTHER REFERENCES The FreezingPreservation of Foods, 1943, by Tressler et al., published by The AviPublishing Co., Inc., New York publishers, pages 486 and 501.

The Freezing Preservation of Foods, 1947, by D. K. Tressler, publishedby The Avi Publishing (10., Inc., page 606.

1. THE METHOD OF PREPARING FRESH RAW LOBSTER IN THE SHELL FOR COLDSTORAGE WHICH COMPRISES HEATING THE EXTERIOR OF THE LOBSTER JUSTSUFFICIENTLY TO SEAR THE SURFACE OF THE MEAT NEXT TO THE SHELL WITHOUTCOOKING THE INTERIOR MEAT, THEREBY LOOSENING THE MEAT FROM THE SHELL,THEN COOLING AND RAPIDLY FREEZING THE LOBSTER.